Portable toilet



FIG. 1 is a front elevation view of a portable toilet showing my new design;

FIG. 2 is a rear elevation view thereof;

FIG. 3 is a side elevation view thereof;

FIG. 4 is a top plan view thereof;

FIG. 5 is a bottom plan view thereof;

FIG. 6 is an isometric view thereof; and,

FIG. 7 is an opposite side elevation view thereof.

The broken lines in the drawings depict environmental subject matter only and form no part of the claimed design. 

The ornamental design for a portable toilet, as shown and described. 